The objective is to understand the role of the mechanical (fluid- elastic) activity of the cochlea in the processing of acoustical signals. The approach consists of formulating a physical model which simulates certain features of the cochlea, and then obtaining, through asymptotic approximation techniques, simple, but sufficiently accurate, solutions to the exact equations governing the physical model. A previous model for BM motion gives excellent correlation with cochlear data for phase, arrival time, and place of maximum displacement; but does not give the proper decay of the traveling wave. In the proposed investigation, physical models for the organ of Corti will be treated. It appears that the flexibility of the rods of Dieter and the flow of Cortilymph give a substantially greater damping effect. Experiments are planned to determine the properties of the fluid flow around the outer hair cell cilia. Several additional aspects of the mechanical function will be treated. Preliminary tests indicate that the asymmetric shape of the cilia causes a surprising rectification of the fluid folw, which could be of great significance.